1. Field of the Invention
Disclosed herein is a temperature movable structure of a superconducting cable terminal. More particularly, disclosed herein is a temperature movable structure of a superconducting cable terminal, in which the assembling and insulating structures of a conductor installed in the temperature movable structure are improved as new ones, so that the assembling property, structural strength and insulation strength of the temperature movable structure can be enhanced, and the deformation of the conductor due to thermal contraction and expansion can be reduced.
2. Description of the Related Art
A general superconducting cable terminal has sections of a high temperature portion, a temperature movable portion and an extremely low temperature portion in the direction from its top to its bottom. A conductor bar is installed in each of the sections that respectively form the high temperature portion, the temperature movable portion and the extremely low temperature portion.
For insulation of the terminal, it is general that gaseous nitrogen is contained in the temperature movable portion, insulating oil or gas is contained in the high temperature portion, and liquid nitrogen is contained in the extremely low temperature portion.
The general superconducting cable terminal having the aforementioned configuration has a structure in which only a solid insulator of which insulation is broken down cannot be removed or separated from a conductor bar even when the insulation breakdown for the solid insulator occurs in the temperature movable portion with a high incidence of insulation accidents. Therefore, it is necessary that the solid insulator and the conductor bar should be separately manufactured as new ones and that the process of surrounding the solid insulator around the surface of the conductor bar should be performed again. Hence, it is not easy to maintain and repair the superconducting cable terminal. Accordingly, cost for maintenance and repair is increased.
Since a conductor bar used conventionally is formed into a structure in which its internal section is filled, its heat transfer area is wide. Therefore, the conductor bar is seriously deformed due to excessive heat transfer in thermal contraction or expansion. Accordingly, the solid insulator is broken, and therefore, insulation breakdown occurs.